A diaphragm is used for, for example, cars, gas appliances, and air conditioners as a part of a pump, carburetor, bulb, and the like.
Patent Document 1 discloses a diaphragm for filter press which is made of a vulcanized rubber with high thermal conductivity which comprises: 100 parts by weight of a raw material rubber such as polyisoprene rubber; and 100 to 250 parts by weight of aluminum hydroxide and/or magnesium hydroxide.
Patent Document 2 discloses a diaphragm containing a vulcanized rubber and reinforcement fibers for the rubber. The reinforcement fibers are in the form of a fabric for rubber reinforcement, either the warps or the wefts are woven to have a lower density portion and a higher density portion, and the higher density portion is in the peripheral part while the lower density portion is in the central part, in order to provide a diaphragm which has an excellent uniformity in deformation by high sealing pressure, has a low rigidity owing to the lower fabric density of the central part than that of the peripheral part, and has an excellent uniformity in rubber thickness as a molded product.
Patent Document 3, in order to provide a diaphragm for fuel system excellent in dimensional accuracy, discloses a diaphragm for fuel system produced from a modified acrylic rubber composition containing a specific acrylic rubber and polyvinylidene fluoride in a predetermined proportion.